interface Deno.MemoryUsage
rss: number
The number of bytes of the current Deno's process resident set size,
which is the amount of memory occupied in main memory (RAM).
heapTotal: number
The total size of the heap for V8, in bytes.
heapUsed: number
The amount of the heap used for V8, in bytes.
external: number
Memory, in bytes, associated with JavaScript objects outside of the
JavaScript isolate.